Display device

ABSTRACT

A display device includes a substrate including a first area, a second area, and a bending area. A plurality of first wires are positioned in the first area. A plurality of second wires are positioned in the second area. An insulating layer is positioned in the bending area. A plurality of connecting wires are disposed on the insulating layer. Each of the connecting wires is connected with at least one of the first wires and at least one of the second wires. Each of the connecting wires includes a first portion and a second portion alternatingly arranged along an extending direction of the connecting wires. A width of the first portion is wider than a width of the second portion in a direction perpendicular to the extending direction each of the connecting wires.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/701,237 filed on Dec. 3, 2019, which is a continuation of U.S. patentapplication Ser. No. 15/856,886 filed on Dec. 28, 2017, now U.S. Pat.No. 10,497,770 issued on Dec. 3, 2019, which claims priority to KoreanPatent Application No. 10-2017-0061857 filed in the Korean IntellectualProperty Office on May 18, 2017, the disclosures of which areincorporated by reference herein in their entireties.

Technical Field

Exemplary embodiments of the present invention relate to a displaydevice, and more particularly to a display device including connectingwires with varying widths.

Discussion of Related Art

A display device such as an organic light emitting diode display and aliquid crystal display may include various wires and elements. Displaydevices may have relatively high resolution.

Forming relatively more wires and elements on a substrate in apredetermined area may increase the resolution of the display device.Widths of wires may be reduced in a particular area. However, theadhesion between the wires and a lower layer may be weakened as an areaof the wires contacting the lower layer becomes smaller, which mayincrease a likelihood that the wires are lifted.

SUMMARY

A display device according to an exemplary embodiment of the presentinvention includes a substrate including a first area, a second area,and a bending area between the first area and the second area. Aplurality of first wires are positioned in the first area. A pluralityof second wires are positioned in the second area. An insulating layeris positioned in the bending area. A plurality of connecting wires aredisposed on the insulating layer. Each of the plurality of connectingwires is connected with at least one of the plurality of first wires andat least one of the plurality of second wires. Each of the plurality ofconnecting wires includes a first portion and a second portionalternatingly arranged along an extending direction of each of theplurality of connecting wires. A width of the first portion is widerthan a width of the second portion in a direction perpendicular to theextending direction each of the plurality of connecting wires.

At least one of the plurality of connecting wires may be in directcontact with the insulating layer.

At least one of the plurality of connecting wires may includes a metalmaterial, and the insulating layer may include an organic insulatingmaterial.

The first portion may protrude from opposite sides of the second portionalong the direction perpendicular to the extending direction of each ofthe plurality of connecting wires.

The first portion may protrude from one side of the second portion.

The plurality of connecting wires may include a first connecting wireand a second connecting wire which are adjacent to each other. The firstportion of the first connecting wire may be disposed in parallel withthe second portion of the second connecting wire along the directionperpendicular to the extending direction of each of the plurality ofconnecting wires.

The first portion of each of the plurality of connecting wires may havea smaller width along the extending direction of each of the pluralityof connecting wires than that of the second portion.

The insulating layer may include a plurality of peaks and a plurality ofvalleys. The first portion may be disposed on one of the plurality ofpeaks.

The first portion may be disposed over at least two of the plurality ofpeaks.

At least one of the plurality of connecting wires may be a data signalline for transferring data signals.

A display device according to an exemplary embodiment of the presentinvention includes a substrate including a bending area that is bentaround a bending axis that is in parallel with a first direction. A wirelinearly extends in a second direction that crosses the first directionin the bending area. The wire includes a first portion having a firstwidth along the first direction and a second portion having a secondwidth along the first direction. A first insulating layer is disposedbetween the substrate and the wire in the bending area. The firstinsulating layer includes an organic insulating material. The firstwidth of the first portion is wider than the second width of the secondportion.

The wire may include a metal material. A lower surface of the wire maybe in direct contact with an upper surface of the first insulatinglayer.

A lower surface of the first insulating layer may be in direct contactwith an upper surface of the substrate.

A second insulating layer may be disposed on the first insulating layerand may include an organic insulating material. An upper surface of thewire may be in direct contact with a lower surface of the secondinsulating layer.

A second insulating layer may be disposed on the first insulating layerand may include an organic insulating material. A lower surface of thewire may be in direct contact with an upper surface of the secondinsulating layer.

The first portion and the second portion may be alternatingly arrangedalong an extending direction of the wire.

A difference between the first width and the second width may be about 1μm or more.

The first insulating layer may include a plurality of peaks and aplurality of valleys that are alternatingly formed along the seconddirection. The first portion may be disposed on one of the plurality ofpeaks.

The first portion may be disposed over at least two of the plurality ofpeaks.

The wire might not include an opening therein.

According to an exemplary embodiment of the present invention, it ispossible to secure a wiring structure with relatively strong adhesion toa lower layer below the wiring structure while forming a relativelylarge number of wires in a limited area. Thus, a relativelyhigh-resolution display device may be formed with increased reliabilityof wires.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other features of the present invention will become moreapparent by describing in detail exemplary embodiments thereof withreference to the accompanying drawings, in which:

FIG. 1 is a top plan view schematically illustrating an un-bent displaydevice according to an exemplary embodiment of the present invention.

FIG. 2 is a side view of the display device illustrated in FIG. 1 afterbeing bent.

FIG. 3 and FIG. 4 are each enlarged views illustrating a region E inFIG. 1 according to an exemplary embodiment of the present invention.

FIG. 5 is a cross-sectional view taken along a line V-V′ in FIG. 1according to an exemplary embodiment of the present invention.

FIG. 6 is a cross-sectional view taken along a line VI-VI′ in FIG. 1according to an exemplary embodiment of the present invention.

FIG. 7 is a cross-sectional view taken along a line V-V′ in FIG. 1according to an exemplary embodiment of the present invention.

FIGS. 8 to 11 are each enlarged views illustrating a region E in FIG. 1according to an exemplary embodiment of the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Exemplary embodiments of the present invention will be described belowin more detail with reference to the accompanying drawings. In thisregard, the exemplary embodiments may have different forms and shouldnot be construed as being limited to the exemplary embodiments of thepresent invention described herein.

Like reference numerals may refer to like elements throughout thespecification and drawings.

It will be understood that when a component, such as a layer, a film, aregion, or a plate, is referred to as being “on” another component, thecomponent may be directly on the other component or interveningcomponents may be present.

FIG. 1 is a top plan view schematically illustrating an un-bent displaydevice according to an exemplary embodiment of the present invention.FIG. 2 is a side view of the display device illustrated in FIG. 1 afterbeing bent. FIG. 3 and FIG. 4 are each enlarged views illustrating aregion E in FIG. 1 according to an exemplary embodiment of the presentinvention.

Referring to FIG. 1, a display device according to an exemplaryembodiment of the present invention may include a display panel 10 and aflexible printed circuit film 20 connected with the display panel 10.

The display panel 10 in which elements for displaying images are formedon a substrate may include a display area DA for displaying the images,and a non-display area NA positioned at an outer circumference of thedisplay area DA, in which elements and/or wires for generating and/ortransferring various signals that are applied to the display area DA arepositioned. Although a lower area of the display panel 10 is illustratedin FIG. 1 as the non-display area NA, left and right edges and/or anupper edge of the display panel 10 may serve as the non-display area NA.

Pixels PX may be arranged, for example, in a matrix form in the displayarea DA of the display panel 10. Signal lines such as gate lines anddata lines may be positioned in the display area DA. The gate lines mayextend substantially in a first direction D1 (e.g., a row direction),and the data lines may extend substantially in a second direction D2(e.g., a column direction) crossing the first direction D1. Each of thepixels PX may be connected to a gate line and a data line to receive agate signal and a data signal therefrom. In the case of an organic lightemitting diode display, driving voltage lines, which extend, forexample, in the second direction D2 to transmit a driving voltage to thepixels PX, may be positioned in the display area DA.

The display area DA may include a touch sensor layer for sensing acontact or non-contact touch of a user. Although the display area DA isillustrated to have a quadrangular shape, the display area DA may havevarious shapes such as a polygonal shape, a circular shape, or anelliptical shape, for example.

A pad unit PP including pads for receiving signals from the outside maybe positioned in the non-display area NA of the display panel 10. Thepads of the pad unit PP may be connected with the wires disposed in thenon-display area NA. A first end of the flexible printed circuit film 20may be bonded to the pad unit PP. A second end of the flexible printedcircuit film 20 may be connected with, e.g., an external printed circuitboard (PCB) to transmit a signal such as image data.

A driving device for generating and/or processing various signals fordriving the display panel 10 may be positioned in the non-display areaNA, and may be positioned in the flexible printed circuit film 20 bondedto the pad unit PP. The driving device may include a data driver whichapplies a data signal to the data line, a gate driver which applies agate signal to the gate line, and a signal controller which controls thegate driver.

The data driver may be positioned in the non-display area NA between thedisplay area DA and the pad unit PP in a form of an integrated circuitchip 40. The data driver may be positioned in the flexible printedcircuit film 20 in a form of an integrated circuit chip to be connectedto the pad unit PP in a form of a tape carrier package (TCP). The gatedriver may be provided in a form of an integrated circuit chip, or maybe integrated in the non-display area of the left/right edge of thedisplay panel 10. The signal controller may include an integratedcircuit chip 40, or may be provided as a separate integrated circuitchip

Referring to FIG. 1 and FIG. 2, the display panel 10 may include abending area BA between the display area DA and the pad unit PP. Thebending area BA may be bent around a bending axis BX. Referring to FIG.2, the bending area BA is a region that is bendable in a predeterminedcurvature radius in the display panel 10. The bending area BA may bepositioned to cross the display panel 10 in a first direction D1. Thedisplay panel 10 may be bent around the bending axis BX parallel to thefirst direction D1, so that the flexible printed circuit film 20 may bepositioned behind the display area DA.

While the bending area BA may be bent around one bending axis BX,exemplary embodiments of the present invention are not limited thereto,and the bending area BA may be bent about two or more bending axes.Although the bending area BA may be positioned in the non-display areaNA, exemplary embodiments of the present invention are not limitedthereto, and the bending area BA may extend over the display area DA andthe non-display area NA, or may be positioned in the display area DA.Wires for transferring signals inputted through the pads of the pad unitPP or signals generated in the driver to the display area DA may bedisposed on an insulating layer including an organic material.

The display panel 10 may include the bending area BA, a first area A1positioned at a first side of the bending area BA, and a second area A2positioned at a second side of the bending area BA. The first area A1,the bending area BA, and the second area A2 may be arranged in thisstated order along the second direction D2. The first area A1 mayinclude the display area DA, and the integrated circuit chip 40 and thepad unit PP may be positioned in the second area A2. According to anexemplary embodiment of the present invention, the non-display area NAmay include a portion of the first area A1 adjacent to the bending areaBA, the bending area BA, and the second area A2. A supporter or anadhesive member for maintaining a predetermined state may be positionedbetween the first area A1 and the second area A2.

Wires disposed in the bending area BA may be connected with wires and/orterminals positioned in the first area A1 and the second area A2, andmay be referred to as “connecting wires.”

The connecting wires (see, e.g., connecting wires 179 discussed in moredetail below) may include data signal lines for transferring datasignals to the data lines. As the resolution of the display deviceincreases, a number of pixel columns may increase, so that a number ofthe data signal lines may also increase. Thus, widths of the data signallines may be reduced as the resolution of the display device increases.The connecting wires may be positioned to cross the bending area BA, toextend in a direction substantially parallel to the second direction D2or obliquely with respect to the second direction. When the bending areaBA is bent, the connecting wires may be bent. The connecting wires mayinclude a metal having relatively high flexibility. As the flexibilityof the connecting wires increases, an occurrence of stress to the wires(e.g., when bent) may be reduced, thus reducing the risk ofdeterioration or disconnection during bending.

Referring to FIG. 3, wires 179 positioned in the bending area BA areillustrated. The wires 179 may be positioned relatively closely to eachother, and a maximum width (x+α) of the wires 179 may be, e.g., about 15μm or less, for example, about 10 μm or less, or about 5 μm or less. Anoverall extending direction of the wires 179 may be along asubstantially straight line. The wires 179 may include a relatively wideextended portion EA and a relatively narrow reduced portion RA, whichare alternatingly formed along an extending direction of the wires 179.In one wire 179, each of the extended portions EA may have substantiallya same size as each other. According to an exemplary embodiment of thepresent invention, each of the extended portions EA may have differentsizes from each other. In one wire 179, the extended portions EA mayhave substantially a same space interval therebetween or different spaceintervals therebetween along the extending direction of the wire 179. Inone wire 179, each of the reduced portions RA may have substantially asame size as each other. According to an exemplary embodiment of thepresent invention, each of the reduced portions RA may have differentsizes from each other. In one wire 179, the reduced portions RA may havesubstantially a same space interval therebetween or different spaceintervals therebetween along the extending direction of the wire 179.

A width of the extended portion EA may be x+α μm, and a width of thereduced portion RA may be x−α μm. Herein, “x” corresponds to a referencewidth according to a predetermined width, and “α” is greater than 0.Adhesion to the insulating layer positioned below the wires 179 may beincreased compared with the case where the wires 179 are constantlyformed to have a width of x μm. The adhesion increases as the contactarea increases, and since the extended portions EA of the wires 179 arein direct contact with the insulating layer over a relatively largearea, the adhesion at the extended portions EA is relatively high. Incontrast, the reduced portions RA are in direct contact with theinsulating layer over a relatively small area, and thus the adhesion atthe extended portions EA is relatively low. However, the extendedportions EA are strongly attached to the insulating layer, and thus thereduced portions RA positioned between the extended portions EA may beprevented from being lifted to suppress the wires 179 from being liftedfrom the insulating layer.

As an example, the wires 179 may be formed by depositing a metalmaterial on the insulating layer by a sputtering method and then byusing a photolithography process. In the photolithography process, ametal material layer is etched by using a photoresist as a mask to formthe wires 179, and then the photoresist is removed through a wet process(e.g., stripping, and washing). In this case, the wires 179 may bepartially lifted in the insulating layer. When the wires 179 are lifted,disconnection or degradation may occur. According to an exemplaryembodiment of the present invention, the adhesion to the insulatinglayer disposed below the wires 179 may be increased by partially widelyforming the wires 179, thus reducing or eliminating lifting or partiallifting of the wires 179.

As an example, when a width of the wires 179 is 3.5 μm or less, thewires 179 may be lifted. Accordingly, “x+α” corresponding to the widthof the extended portion EA may be greater than 3.5, and “x−α” may beequal to or smaller than 3.5. “α” may be equal to or greater than 0.5,and thus a width difference between the extended portion EA and thereduced portion RA may be 1 μm or more. Sizes of the extended portion EAand the reduced portion RA may be variously designed in considerationof, for example, the adhesion of the wires 179 to the insulating layer,and/or resistance of the wires 179.

The extended portions EA and the reduced portions RA of the wires 179may be complementarily formed between the adjacent wires 179 such thatan extended portion EA of a first wire faces a reduced portion RA of anadjacent wire along a direction perpendicular to the extending directionof the wire 170. For example, in two adjacent wires 179, the extendedportion EA of a first wire 179 and the reduced portion RA of a secondwire 179 may be disposed in parallel. Accordingly, the extended portionsEA and the reduced portions RA of the wires 179 may be alternatingly andrepeatedly disposed along the first direction one by one. Thus, it ispossible to secure an area for forming the extended portions EA whilemaintaining a distance between the wires 179, by complementarily formingthe extended portions EA and the reduced portions RA of the adjacentwires 179. When the width of the wires 179 is generally increased, thedistance between the adjacent wires 179 is reduced to increase thecoupling capacitance, and thus image deterioration caused by crosstalkmay occur and a short circuit between the wires 179 may occur. Accordingto an exemplary embodiment of the present invention, the intervalbetween the adjacent wires 179 may be made substantially constant overan entire length of the wires 179. The distance between the adjacentwires 179 may be y μm. Herein, “y” may be 2.5 pm or more, but may besmaller than 2.5 μm, and may be modified depending on design rules.

According to an exemplary embodiment of the present invention, theextended portion EA of each of the connecting wires 179 of the pluralityof connecting wires may have a smaller width along the extendingdirection of the plurality of connecting wires than that of the reducedportion RA.

According to an exemplary embodiment of the present invention, theextended portion EA includes portions protruded at opposite sides of thereduced portion RA based on a central axis of the longitudinal directionof the connecting wire 179, but exemplary embodiments of the presentinvention are not limited thereto. For example, referring to FIG. 4, theextended portion EA may include a portion protruded toward one side ofthe reduced portion RA. The protruded portion of the extended portion EAmay be alternatingly positioned at right and left sides of the reducedportion RA along the length of the wires 179.

A stacked structure of the display panel 10 and connecting wiresaccording to an exemplary embodiment of the present invention will bedescribed in more detail below based on the bending area BA as well asthe pixels PX of the display panel 10. An organic light emitting diodedisplay will be described in more detail below as an example.

FIG. 5 is a cross-sectional view taken along a line V-V′ in FIG. 1according to an exemplary embodiment of the present invention. FIG. 6 isa cross-sectional view taken along a line VI-VI′ in FIG. 1 according toan exemplary embodiment of the present invention.

Configurations of FIG. 5 and FIG. 6 are substantially the same exceptfor a difference in positions of connecting wires 179 a and 179 b.Referring to FIG. 3 and FIG. 4, the connecting wires 179 a and 179 b aresubstantially the same as the wires 179 described in more detail above.Accordingly, planar shapes of the connecting wires 179 a and 179 b maybe the same as those described above with reference to FIG. 3 or FIG. 4.Thus, duplicative descriptions may be omitted below.

Referring to FIG. 5 and FIG. 6, the display panel 10 may include asubstrate 110 and a plurality of layers and wires formed thereon.Although a relatively large number of pixels may be arranged in thedisplay area DA of the display panel 10, only one pixel is illustratedin FIG. 3. Each pixel may include transistors, a capacitor, and anorganic light emitting diode, but a stacked structure of the displaypanel 10 will be described including a description of one transistor andone organic light emitting diode connected thereto.

The substrate 110 may be a flexible substrate. The substrate 110 mayinclude a polymer such as polyimide, polycarbonate, or polyethyleneterephthalate, but exemplary embodiments of the present invention arenot limited thereto.

A barrier layer 111 and a buffer layer 112 may be disposed on thesubstrate 110 to reduce or eliminate a diffusion of impurities which maycause degradation of semiconductor characteristics, and to reduce oreliminate moisture penetration. The barrier layer 111 and the bufferlayer 112 may include an inorganic insulating material such as a siliconoxide (SiO_(x)) or a silicon nitride (SiN_(x)). The barrier layer 111and the buffer layer 112 may be formed on an entire surface of thesubstrate 110, but need not be disposed on the bending area BA. A layerformed of the inorganic insulating material may be vulnerable tobending, and thus cracks may occur, or it may damage the wiring locatedin the bending area BA. Thus, either of the barrier layer 111 and thebuffer layer 112 may be omitted (e.g., in the bending area BA).

A semiconductor layer 154 of a transistor may be disposed on the bufferlayer 112. The semiconductor layer 154 may include a channel region 152,and a source region 153 and a drain region 155 doped and disposed atopposite sides of the channel region 152. The semiconductor layer 154may include polysilicon, amorphous silicon, or an oxide semiconductor.

A gate insulating layer 140 including an inorganic insulating materialsuch as a silicon oxide or a silicon nitride may be disposed on thesemiconductor layer 154. The gate insulating layer 140 need not bepositioned in the bending area BA.

A gate conductor including a gate line, a gate electrode 124 of thetransistor, first wires 127 a and 127 b, and second wires 129 a and 129b may be disposed on the gate insulating layer 140. The gate conductormay include a metal such as molybdenum (Mo), copper (Cu), aluminum (Al),silver (Ag), chromium (Cr), tantalum (Ta), or titanium, or a metal alloythereof. The gate electrode 124 may overlap the channel region 152 ofthe semiconductor layer 154 along a direction orthogonal to an uppersurface of the substrate 110. The first wires 127 a and 127 b may beconnected to the display area DA (e.g., a data line and a signal linesuch as a driving voltage line), a driver (e.g., a gate driver), and thesecond wires 129 a and 129 b may be connected to a terminal of theintegrated circuit chip 40, and a pad of the pad unit PP.

An interlayer insulating layer 160 may be disposed on the gateinsulating layer 140 and the gate conductor. The interlayer insulatinglayer 160 may include an inorganic insulating material such as a siliconoxide, a silicon nitride, a silicon oxynitride (SiON), or a siliconoxyfluoride (SiOF). The interlayer insulating layer 160 need not bedisposed in the bending area BA.

A first data conductor including a data line, a source electrode 173 anda drain electrode 175 of the transistor, a voltage transfer line 177,and the connecting wire 179 a may be disposed on the interlayerinsulating layer 160. The source electrode 173 and the drain electrode175 may be respectively connected to the source region 153 and the drainregion 155 of the semiconductor layer 154 through contact holes 61 and62 formed in the interlayer insulating layer 160 and the gate insulatinglayer 140. The voltage transfer line 177 may transfer a power-sourcevoltage such as a driving voltage or a common voltage.

The connecting wire 179 a may be positioned in the bending area BA. Theconnecting wire 179 a may be connected with the first wire 127 a througha contact hole 81 formed in the interlayer insulating layer 160 in thefirst area A1, and may be connected with the second wire 129 a through acontact hole 82 formed in the interlayer insulating layer 160 in thesecond area A2. Thus, the first wire 127 a and the second wire 129 awhich are gate conductors may be electrically connected to each other bythe connecting wire 179 a. Thus, a signal output from the integratedcircuit chip 40 and the pad may be transmitted to the display area DA,and the driving device through the second wire 129 a, the connectingwire 179 a, and the first wire 127 a.

As an example, the first data conductor may include a metal such asaluminum (Al), copper (Cu), silver (Ag), gold (Au), platinum (Pt),palladium (Pd), nickel (Ni), molybdenum (Mo), tungsten (W), titanium(Ti), chromium (Cr), or tantalum (Ta), or a metal alloy thereof. Thefirst data conductor may have a multilayer structure, and may have atriple-layer structure including, e.g., a bottom layer (e.g., anancillary layer) for increasing contact properties and an upper layer(e.g., a capping layer) for preventing oxidation. The lower layer andthe upper layer may include titanium (Ti), chromium (Cr), molybdenum(Mo), or tantalum (Ta), for example. The first data conductor may be amultilayer such as titanium/aluminum/titanium (Ti/Al/Ti),titanium/copper/titanium (Ti/Cu/Ti), or molybdenum/aluminum/titanium(Mo/Al/Mo), but exemplary embodiments of the present invention are notlimited thereto. In the bending area BA, a protective layer 165 which isan insulating layer is disposed between the substrate 110 and theconnecting wire 179 a. The protective layer 165 may overlap the gateinsulating layer 140 and the interlayer insulating layer 160 in thefirst area A1 and the second area A2 along the direction orthogonal tothe upper surface of the substrate 110. The protective layer 165 may bein direct contact with the upper surface of the substrate 110 in thebending area BA. The protective layer 165 may include an organicinsulating material. For example, the organic insulating material mayinclude, but is not limited to, a polyimide, an acrylic polymer, or asiloxane-based polymer.

The connecting wire 179 a including a metal material may be disposed onthe protective layer 165 including an organic insulating material.Adhesion of the metal wire to the organic insulating layer may be weakerthan adhesion to the inorganic insulating layer. When a width of theconnecting wire 179 a is reduced to, e.g., 3.5 μm or less, theconnecting wire 179 a may be partially lifted, and thus the connectingwire 179 a may be separated or disconnected. However, as described abovewith reference to FIG. 3 and FIG. 4, in the connecting wire 179 a,extended portions EA and reduced portions RA may be repeatedly formedalong the extending direction of the connecting wire 179 a, and theadhesion may be increased by the extended portions EA, which may reduceor eliminate an occurrence of the connecting wire 179 a being liftedfrom the protective layer 165.

The gate electrode 124, the source electrode 173, and the drainelectrode 175 may form a transistor together with the semiconductorlayer 154. The transistor may be a driving transistor in a pixel of theorganic light emitting diode display. The transistor may be a top-gatetransistor in which the gate electrode 124 is disposed above thesemiconductor 154, but a structure of the transistor is not limitedthereto, and may be variously modified. As an example, the transistormay be a bottom-gate transistor in which the gate electrode ispositioned below the semiconductor layer, or may be a verticaltransistor in which the gate electrode is positioned in a side surfaceof the semiconductor layer.

A first planarization layer 180 a may be disposed on the interlayerinsulating layer 160 and the first data conductor. The firstplanarization layer 180 a may be positioned in and around the bendingarea BA. In the bending area BA, the first planarization layer 180 a maybe disposed on the protective layer 165. According to an exemplaryembodiment of the present invention, the display device need not includethe protective layer 165, and the first planarization layer 180 a may bein direct contact with the substrate 110.

A second data conductor including a driving voltage line 172 and theconnecting wire 179 b may be disposed on the first planarization layer180 a. A second planarization layer 180 b may be disposed on the seconddata conductor.

The first planarization layer 180 a and the second planarization layer180 b may include an organic insulating material such as a polyimide, anacryl-based polymer, or a siloxane-based polymer, but exemplaryembodiments of the present invention are not limited thereto. Forexample, the second data conductor may include a metal such as aluminum(Al), copper (Cu), silver (Ag), gold (Au), platinum (Pt), palladium(Pd), nickel (Ni), molybdenum (Mo), tungsten (W), titanium (Ti),chromium (Cr), or tantalum (Ta), or a metal alloy thereof. The seconddata conductor may be a multilayer, and may have a triple-layerstructure including, e.g., a bottom layer (e.g., an ancillary layer) forincreasing contact properties and an upper layer (e.g., a capping layer)for preventing oxidation. The lower layer and the upper layer mayinclude titanium (Ti), chromium (Cr), molybdenum (Mo), or tantalum (Ta),for example. The second data conductor may be a multilayer such astitanium/aluminum/titanium (Ti/Al/Ti), titanium/copper/titanium(Ti/Cu/Ti), or molybdenum/aluminum/titanium (Mo/Al/Mo), but exemplaryembodiments of the present invention are not limited thereto.

The connecting wire 179 b may be positioned in the bending area BA. Theconnecting wire 179 b (and the connecting wire 179 a described above)may extend slightly beyond the bending area BA. The connecting wire 179b may be connected with the first wires 127 b through a contact hole 85formed in the first planarization layer 180 a and the interlayerinsulating layer 160 in the first area A1, and may be connected with thesecond wires 129 b through a contact hole 86 formed in the firstplanarization layer 180 a and the interlayer insulating layer 160 in thesecond area A2. Thus, the first wires 127 b and the second wires 129 bwhich are gate conductors may be electrically connected to each other bythe connecting wire 179 b. Thus, a signal output from the integratedcircuit chip 40 and the pad may be transmitted to the display area DA,and the driving device through the second wire 129 b, the connectingwire 179 a, and the first wires 127 b.

The connecting wire 179 b may be disposed on the first planarizationlayer 180 a including the organic insulating material in the bendingarea BA. Similar to the connecting wire 179 a (see, e.g., FIG. 3 andFIG. 4), in the connecting wire 179 b, extended portions EA and reducedportions RA may be repeatedly formed along an extending direction of theconnecting wire 179 b. The adhesion may be increased by the extendedportions EA to prevent the connecting wire 179 b from being lifted fromthe first planarization layer 180 a.

The connecting wire 179 a may be sandwiched between the protective layer165 and the first planarization layer 180 a, and the connecting wire 179b may be sandwiched between the first planarization layer 180 a and thesecond planarization layer 180 b. Thus, in the bending area, theconnecting wire 179 a may be surrounded by the first planarization layer180 a and the protective layer 165 including the organic insulatingmaterial, and the connecting wire 179 b may be surrounded by the secondplanarization layer 180 b and the first planarization layer 180 aincluding the organic insulating material. Thus, the connecting wire 179a and the connecting wire 179 b may be prevented from being damagedduring bending.

According to an exemplary embodiment of the present invention, when theconnecting wires 179 a and 179 b are formed by using a first dataconductor and a second data conductor which are disposed at differentlayers, the connecting wires 179 a and 179 b may be formed as two layersto increase a width of each connecting wire, and thus the resistance maybe reduced. For example, referring to FIG. 1, the connecting wire 179 aand the connecting wire 179 b may be alternatingly disposed in the firstdirection D1 one by one. According to an exemplary embodiment of thepresent invention, the connecting wires may be formed by only using thefirst data conductor or the second data conductor, and thus may onlyinclude the connecting wires 179 a or the connecting wires 179 b.

In the display area DA, a pixel electrode 191 may be disposed on thesecond planarization layer 180 b. The pixel electrode 191 of each pixelmay be connected to the drain electrode 175 through a contact hole 83formed in the first planarization layer 180 a and the secondplanarization layer 180 b. The pixel electrode 191 may include areflective conductive material or a transflective conductive material,or may include a transparent conductive material.

A pixel definition layer 360 including an opening that overlaps thepixel electrode 191 along the direction orthogonal to the upper surfaceof the substrate 110 may be disposed on the second planarization layer180 b. The opening of the pixel definition layer 360 may define eachpixel area. The pixel definition layer 360 may include an organicinsulating material. The pixel definition layer 360 may be disposed onthe second planarization layer 180 b in the bending area BA.

An emission member 370 may be disposed on the pixel electrode 191. Theemission member 370 may include a first organic common layer, anemission layer, and a second organic common layer which are stacked insequence. The first organic common layer may include at least one of ahole-injection layer and a hole-transporting layer. The emission layermay include an organic material which uniquely emits light of one ofprimary colors such as red, green, or blue, and may have a structure inwhich a plurality of organic material layers emitting light of differentcolors are stacked. The second organic common layer may include at leastone of an electron-transporting layer or an electron-injection layer.

A common electrode 270 for transferring a common voltage may be disposedon the emission member 370. The common electrode 270 may include atransparent conductive material such as ITO or IZO, or may be formed bythinly stacking a metal such as calcium (Ca), barium (Ba), magnesium(Mg), aluminum (Al), or silver (Ag), to have relatively lightpermeability. The pixel electrode 191, the emission member 370, and thecommon electrode 270 of each pixel may be a light-emitting element whichis an organic light emitting diode.

An encapsulation layer 390 may be disposed on the common electrode 270.The encapsulation layer 390 may encapsulate the emission member 370 andthe common electrode 270 to prevent permeation of external moisture oroxygen. The encapsulation layer 390 may include at least one layerincluding an inorganic material, and may further include at least onelayer including an organic material. The encapsulation layer 390 neednot be disposed in the bending area BA. A polarization layer forpreventing external light reflection may be disposed on theencapsulation layer 390. The polarization layer need not overlap thebending area BA. In the bending area BA, a bending protective layer forreleasing and protecting against tensile stress may be disposed on thepixel definition layer 360. The bending protective layer may be referredto as a stress neutralization layer.

A protection film 500 may be positioned below the substrate 110. Theprotection film 500 may be attached to the substrate 110 (e.g., aflexible substrate 110) by an adhesive such as a pressure sensitiveadhesive (NA) or an optically clear adhesive (OCA). The protection film500 may include a polymer such as polyethylene terephthalate,polyethylene naphthalate, polyimide, or polyethylene sulfide. Theprotection film 500 need not be positioned in the bending area BA, whichmay reduce a bending stress.

FIG. 7 is a cross-sectional view taken along a line V-V′ in FIG. 1according to an exemplary embodiment of the present invention. FIGS. 8to 11 are each enlarged views illustrating a region E in FIG. 1according to an exemplary embodiment of the present invention.

Referring to FIG. 7, the protective layer 165 may be disposed betweenthe substrate 110 and the connecting wire 179 a in the bending area BA.Thus, the connecting wire 179 a may be disposed on the protective layer165. Unlike in the exemplary embodiment of FIG. 5, an upper surface ofthe protective layer 165 is not flatly formed to include an unevenportion thereon. A peak U1 and a valley U2 of the protective layer 165may extend in the first direction D1 that is substantially parallel withthe bending axis BX. Thus, the peak U1 and the valley U2 of theprotective layer 165 may be alternatingly arranged one by one in thesecond direction D2. The connecting wire 179 a may be conformally formedon the protective layer 165 by the action of this uneven structure ofthe protective layer 165 to form a shape including multiple curves(e.g., a wrinkle shape). The wrinkle of the connecting wire 179 a may beunfolded like a bellows of an accordion when the bending area BA isbent, and thus a risk of disconnection of the connecting wire 179 a maybe further reduced. Even though the connecting wire 179 a is wrinklyformed, it may extend substantially linearly in a plan view.

A gate conductor including a gate line, the gate electrode 124 of thetransistor, a first wire 127, and second wire 129 is disposed on thegate insulating layer 140. The gate conductor may include a metal suchas molybdenum (Mo), copper (Cu), aluminum (Al), silver (Ag), chromium(Cr), tantalum (Ta), or titanium, or a metal alloy thereof.

The driving voltage line 172 may be positioned at a same layer as thatof the source electrode 173 and the drain electrode 175 of thetransistor. Thus, a first data conductor including the driving voltageline 172 as well as the data line, the source electrode 173 and thedrain electrode 175, and the voltage transfer line 177, and theconnecting wire 179 a may be disposed on the interlayer insulating layer160. A planarization layer 180 including an organic insulating materialmay be disposed on the first conductor. The connecting wire 179 a may besurrounded by the protective layer 165 and the planarization layer 180to prevent damage during bending. However, as in the exemplaryembodiment of FIG. 5, the display device may include a firstplanarization layer and a second planarization layer above the firstconductor, and the driving voltage line 172 may be disposed between thefirst planarization layer and the second planarization layer.

The connecting wire 179 a may be formed by depositing a metal materialon the protective layer 165 and then using a photolithography process.When the connecting wire 179 a is formed, a photoresist portionpositioned on the peak U1 may be exposed more than a photoresist portionpositioned on the valley U2. Thus, even when the connection wirings 179a having a uniform width are intended to be formed, a wire width of aportion of the connecting wire 179 a disposed on the peak U1 may besmaller than that of a portion of the connecting wire 179 a disposed onthe valley U2. Thus, it is possible to compensate for the weakness ofthe adhesion caused by reduction in the wire width by widely forming theportion of the connecting wire 179 a positioned on the peak U1. Examplesthereof are described in more detail below with reference to FIGS. 8 to11.

Referring to FIG. 8, in the connecting wire 179 a, the extended portionsEA and the reduced portions RA may be repeatedly formed along theextending direction of the connecting wire 179 a. The extended portionsEA may be disposed on the peak U1 of the protective layer 165. Thus, itis possible to increase the adhesion of the connecting wire 179 a bywidely forming a portion of the connecting wire 179 a positioned on thepeak U1 of the protective layer 165.

The extended portions EA may be disposed on all peaks U1 of theprotective layer 165, but the reduced portion RA may be disposed on apeak U1. For example, referring to FIG. 8, the reduced portions RA maybe positioned over two valleys U2 and the peak U1 therebetween, and maybe positioned over a larger number of valleys U2 and peaks U1.

A shape, size, and interval of the extended portions EA and the reducedportions RA of the connecting wire 179 a may be variously modified. Forexample, referring to FIG. 9, the extended portions EA may be formed toinclude a portion that protrudes toward one side of the reduced portionsRA. Referring to FIG. 10 and FIG. 11, the extended portions EA may beformed over a plurality of peaks U1 of the protective layer 165 andvalleys U2 therebetween.

While the present invention has been shown and described with referenceto the exemplary embodiments thereof, it will be apparent to those ofordinary skill in the art that various changes in form and detail may bemade thereto without departing from the spirit and scope of the presentinvention.

What is claimed is:
 1. A display device comprising: a first areaincluding a display area in which pixels are arranged; a second areaincluding a pad unit in which pads are arranged; and a third areabetween the first area and the second area and including a bending area,wherein the third area includes a first inorganic insulating layer, asecond inorganic insulating layer on the first inorganic insulatinglayer, and an organic insulating layer on the second inorganicinsulating layer, and a wire on the organic insulating layer, whereinthe first inorganic insulating layer includes a first opening having afirst width, and the second inorganic insulating layer includes a secondopening overlapping the first opening and having a second widthdifferent from the first width, and wherein the wire includes at leastone protrusion protruding in a direction perpendicular to an extendingdirection of the wire.
 2. The display device of claim 1, wherein an edgeof the first insulating layer adjacent to the first opening and an edgeof the second insulating layer adjacent to the second opening form astep shape.
 3. The display device of claim 1, wherein the first openingthe second opening are disposed at least in the bending area.
 4. Thedisplay device of claim 1, wherein organic layer is disposed at leastwithin the first opening.
 5. The display device of claim 1, wherein alower surface of the wire directly contacts an upper surface of theorganic layer.
 6. The display device of claim 1, further comprises: aconductor disposed between the first inorganic layer and the secondinorganic layer, wherein the wire is connected to the conductor througha hole in the second inorganic layer.
 7. The display device of claim 1,wherein each of the pixels includes a transistor and a light emittingdiode connected to the transistor.
 8. A display device comprising: afirst area including a display area in which pixels are arranged; asecond area including a pad unit in which pads are arranged; and a thirdarea between the first area and the second area and including a bendingarea, wherein the third area includes a first inorganic insulatinglayer, a second inorganic insulating layer on the first inorganicinsulating layer, and an organic insulating layer on the secondinorganic insulating layer, and a wire on the organic insulating layer,wherein the first inorganic insulating layer includes a first openinghaving a first width, and the second inorganic insulating layer includesa second opening overlapping the first opening and having a second widthdifferent from the first width, and wherein the wire includes at leastone protrusion and at least one recess which are alternatively arrangedon one side of the wire along an extending direction of the wire.
 9. Thedisplay device of claim 8, wherein an edge of the first insulating layeradjacent to the first opening and an edge of the second insulating layeradjacent to the second opening form a step shape.
 10. The display deviceof claim 8, wherein the first opening the second opening are disposed atleast in the bending area.
 11. The display device of claim 8, whereinorganic layer is disposed at least within the first opening.
 12. Thedisplay device of claim 8, wherein a lower surface of the wire directlycontacts an upper surface of the organic layer.
 13. The display deviceof claim 8, further comprises: a conductor disposed between the firstinorganic layer and the second inorganic layer, wherein the wire isconnected to the conductor through a hole in the second inorganic layer.14. The display device of claim 8, wherein each of the pixels includes atransistor and a light emitting diode connected to the transistor.
 15. Adisplay device comprising: a first area including a display area inwhich pixels are arranged; a second area including a pad unit in whichpads are arranged; and a third area between the first area and thesecond area and including a bending area, wherein the third areaincludes a first inorganic insulating layer, a second inorganicinsulating layer on the first inorganic insulating layer, and an organicinsulating layer on the second inorganic insulating layer, and wires onthe organic insulating layer, wherein the first inorganic insulatinglayer includes a first opening having a first width, and the secondinorganic insulating layer includes a second opening overlapping thefirst opening and having a second width different from the first width,wherein the wires include a first wire and a second wire adjacent toeach other, the first wire includes first protrusions protruding towardsthe second wire, and the second wire includes second protrusionsprotruding towards the first wire, and wherein the first protrusions andthe second protrusions are arranged in a zigzag shape along an extendingdirection of the wires.
 16. The display device of claim 15, wherein anedge of the first insulating layer adjacent to the first opening and anedge of the second insulating layer adjacent to the second opening forma step shape.
 17. The display device of claim 15, wherein the firstopening the second opening are disposed at least in the bending area.18. The display device of claim 15, wherein organic layer is disposed atleast within the first opening.
 19. The display device of claim 15,wherein a lower surface of the wire directly contacts an upper surfaceof the organic layer.
 20. The display device of claim 15, furthercomprises: a conductor disposed between the first inorganic layer andthe second inorganic layer, wherein the wire is connected to theconductor through a hole in the second inorganic layer.